Ok lets see. . .
| Step | Action | Result |
|---|---|---|
| 1. | SSH into zynthian (root/raspberry) | Ok |
| 2. | > cd /etc/X11/xorg.conf.d | Ok, files in there … 99-calibration.conf, 99-fbdev.conf |
| 3. | > cp 99-calibration.conf 99-calibration.conf.backup | backup your current config |
| 4. | > apt-get install xserver-xorg-input-evdev | This package provides the driver for input devices using evdev, the Linux kernel’s event delivery mechanism. This driver allows for multiple keyboards and mice to be treated as separate input devices.—I appear to already have this |
| 5. | > apt-get install -y xinput-calibrator | A generic touchscreen calibration program for X.Org —I’ve already got it but I’ve played around a bit |
| 6. | > apt-get install -y bc | GNU bc arbitrary precision calculator language, and I’ve got that  |
| 7. | 3. copy and paste bash script from link above, create this as “calib” script | (using vi [grrrr]… nano is a much easier windows like tool for people who have issues with vi . . . :-). Type nano calib, cut and paste the code into it. Cntrl O to write it Cntrl X to exit …)add this as first line on script: |
| 8. | add export DISPLAY=:0.0 to script first line | Easy withing nano . . .  |
| 9. | chmod 755 calib | make it executable; I agree with @Baggypants |
| 10. | > ./calib | 6. calibration will popup on screen, follow instructions and Play tap the dot |
| 11. | nano 99-calibration.conf | 7. calibration script will end up with output which should go into /etc/X11/xorg.conf.d/99-calibration.conf [BEWARE! script recommends different file names, IDK if will work then] i already had details for this in the file so I overwrote them |
Directly after calibration all seems good !!!
echo setting up the touchscreen
export DISPLAY=:0.0
xinput set-prop ‘ADS7846 Touchscreen’ ‘Coordinate Transformation Matrix’ 1.06666775175377203405 0 -.04500398769511222513 0 -1.09588468420260530760 1.05137037842176552231 0 0 1
So I reboot …
Sadly E & W are still reversed . . .but I will retry with a clean build as this is a fairly corrupted zynthian-touch.local . . . .
same with calling the file 98-calibration.conf . . . sadly … 
My script fixes it but presumably renders up the not quite accurate scaling factors. . .
So I’ve copied these values into my touch script and they do renerder up a pretty accurate step sequence grid … So from my perspective, it generates a decent matrix but I haven’t found where this should be applied.
Almost right
So in my case it sets the mechanism u correctly but it’s getting it’s start up settings from somewhere else. . .
I will try with a clean image, as this is a zynthian-touch.local that has had a certain amount of ‘persuasion’ …
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